586 
DR. ANDREWS ON THE CONTINUITY OE THE 
Table YI. — Carbonic Acid at 48°T. 
a. 
t. 
, 
f. 
i. 
] 
62*60 
15-67 
1 
86*45 
47-95 
231-5 
1 
68-46 
15-79 
99*39 
48-05 
201-4 
75*58 
15-87 
117*8 
48-12 
170-0 
1 
84-35 
15-91 
1 
146*8 
48-25 
136-5 
1 
95-19 
15-83 
198-5 
48-13 
100-8 
109*4 
16-23 
1 
298-4 
4^ 
GO 
K> 
67-2 
The curve for 32 0, 5 (page 583) resembles closely that for 31°T. The fall is, however, 
less abrupt than at the latter temperature. The range of pressure in the experiments 
at 35°-5 extends from 57 to above 107 atmospheres. The fall is here greatly diminished, 
and it has nearly lost its abrupt character. It is most considerable from 76 to 87 atmo- 
spheres, where an increase of one-seventh in the pressure produces a reduction of volume 
to one-half. At 107 atmospheres the volume of the carbonic acid has come almost into 
conformity with that which it should occupy, if it were derived directly from liquid car- 
bonic acid, according to the law of the expansion of that body for heat. 
The curve for 48°T is very interesting. The fall shown in the curves for lower tem- 
peratures has almost, if not altogether, disappeared, and the curve itself approximates 
to that which would represent the change of volume in a perfect gas. At the same 
time the contraction is much greater than it would have been if the law of Mariotte 
had held good at this temperature. Under a pressure of 109 atmospheres, the carbonic 
acid is rapidly approaching to the volume it would occupy if derived from the expansion 
of the liquid ; and if the experiment had not been interrupted by the bursting of one 
of the tubes, it would doubtless have fallen into position at a pressure of 120 or 130 
atmospheres. 
I have not made any measurements at higher temperatures than 48°T ; but it is clear 
that, as the temperature rises, the curve would continue to approach to that representing 
the change of volume of a perfect gas. 
I have frequently exposed carbonic acid, without making precise measurements, to 
much higher pressures than any marked in the Tables, and have made it pass, without 
break or interruption from what is regarded by every one as the gaseous state, to what 
is, in like manner, universally regarded as the liquid state. Take, for example, a given 
volume of carbonic acid gas at 50° C., or at a higher temperature, and expose it to 
increasing pressure till 150 atmospheres have been reached. In this process its volume 
will steadily diminish as the pressure augments, and no sudden diminution of volume, 
without the application of external pressure, will occur at any stage of it. When the 
full pressure has been applied, let the temperature be allowed to fall till the carbonic 
